CA1297613C - Composition for forming hydrophilic film on aluminum - Google Patents
Composition for forming hydrophilic film on aluminumInfo
- Publication number
- CA1297613C CA1297613C CA000533702A CA533702A CA1297613C CA 1297613 C CA1297613 C CA 1297613C CA 000533702 A CA000533702 A CA 000533702A CA 533702 A CA533702 A CA 533702A CA 1297613 C CA1297613 C CA 1297613C
- Authority
- CA
- Canada
- Prior art keywords
- water
- weight
- alkali metal
- molecular
- soluble
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
- C23C22/60—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using alkaline aqueous solutions with pH greater than 8
- C23C22/66—Treatment of aluminium or alloys based thereon
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/24—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing alkyl, ammonium or metal silicates; containing silica sols
- C04B28/26—Silicates of the alkali metals
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
- C04B2103/10—Accelerators; Activators
- C04B2103/14—Hardening accelerators
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
- C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
- C04B2111/00482—Coating or impregnation materials
- C04B2111/00525—Coating or impregnation materials for metallic surfaces
Abstract
ABSTRACT OF THE DISCLOSURE
A composition for forming a hydrophilic film on aluminum comprises an alkali silicate, an inorganic hardening agent and a water-soluble organic high-molecular-weight compound. The composition is useful for aluminum fin materials for producing heat exchanger fins, aluminum products such as aluminum heat exchangers comprising fins and tubes in combination, and materials of such products. The high-molecular-weight compounds effectively prevents the alkali silicate from giving off a cement odor and also sustains over a prolonged period of time the hydrophilic properties of the film prepared from the alkali silicate and the hardening agent. The composi-tion forms hydrophilic films releasing no cement odor and retaining sustained hydrophilic properties over a long period.
A composition for forming a hydrophilic film on aluminum comprises an alkali silicate, an inorganic hardening agent and a water-soluble organic high-molecular-weight compound. The composition is useful for aluminum fin materials for producing heat exchanger fins, aluminum products such as aluminum heat exchangers comprising fins and tubes in combination, and materials of such products. The high-molecular-weight compounds effectively prevents the alkali silicate from giving off a cement odor and also sustains over a prolonged period of time the hydrophilic properties of the film prepared from the alkali silicate and the hardening agent. The composi-tion forms hydrophilic films releasing no cement odor and retaining sustained hydrophilic properties over a long period.
Description
` ` ~2976~3`
TITLE OF THE INVENTION
COMPOSITION FOR FORMING HYDROPHILIC FILM ON ALUMINUM
BACKGROUND OF THE INVENTION
The present invention relates to a composition for forming a hydrophilic film on aluminum, for example, on the surface of an aluminum fin material for heat exchangers and on the surface of aluminum heat exchangers comprising the combination of fins and tubes.
The term "aluminum" as used herein includes not only pure aluminum but also aluminum alloys.
Generally with heat exchangers, especially with the evaporators of room air conditioners and of air conditioners for motor vehicles, the surface temperature of the fins drops below the dew point of the atmosphere, permitting deposition of water drops on the surface of the fins. The deposition of water drops results in increased resistance to the passage of air and a reduced air flow between the fins to entail a reduced heat , i ............ .
exchange efficiency. Such phenomena occur markedly especially when the fin pitch is decreased to improve the performance of the heat exchanger and to render the exchanger smaller. The wettability of the fin surface greatly influences the heat exchange efficiency. High wettability of the fin surface makes it difficult for the condensed water vapor to form water drops, reducing the resistance to the air flow and increasing the amount of air flow to achieve a higher heat exchange efficiency.
Good wettability further prevents the water deposited on the fins from splashing and the outdoor heat exchanger from frosting.
The wettability of the surface of aluminum fins has heretofore been improved by coating the fin surface with a film using a hydrophilic resin or water glass (alkali silicate, see Examined Japanese Patent Publication SHO 53-48177).
However, thé film of the former material has the drawback of becoming gradually impaired in hydrophilic properties and failing to exhibit sustained resistance to water and oil, while the film prepared from the latter material gives off a cement odor due to the alkali silicate to lower the commercial value of the product.
In view of these problems, the ,main object of the present invention is to provide a composition for ....
~297613 forming a hydrophilic film which gives off no cement odor and which retains sustained hydrophilic properties over a prolonged period of time.
SUMMARY OF THE INVENTION
The composition of the present invention for forming a hydrophilic film on aluminum comprises an alkali silicate, an inorganic hardening agent and a water-soluble organic high-molecular-weight compound.
The hydrophilic film forming composition is used for aluminum fin materials for producing heat exchanger fins, aluminum products such as aluminum heat exchangers comprising the combination of fins and tubes, and materi-als for such products. Suitable aluminum fin materials are coiled materials which can be treated for forming a film and shaped continuously.
The water-soluble organic high-molecular-weight compound serves to effectively prevent the alkali silicate from giving off a cement odor and also to sustain over a prolonged period the hydrophilic properties of the film prepared from the alkali silicate and the inorganic hardening agent.
Thus, ~he composition of the present invention forms hydrophilic films which release no cement odor and retain sustained hydrophilic properties over a prolonged period of time.
.
: . ' , . . .
DETAILED DESCRIPTION OF THE INVENTION
Examples of useful alkali silicates as one of t:he components of the hydrophilic film forming composition are sodium silicate, potassium silicate, lithium silicate, etc.
The alkali silicate acts to impart hydrophilic properties to aluminum. The silicate to be used normally has a SiO2/M2o ratio of at least 1 wherein M is an alkali metal such as lithium, sodium or potassium. Especially preferable are alkali silicates which have a SiO2/M2O ratio of 2 to 5. If the Sio2~M2o ratio is less than 1, SiO2 is smaller than the alkali component in proportion, permitting the alkali component to corrode aluminum markedly.
Further if the proportion of the alkali silicate in the composition is small, the composition fails to form a satisfactory hydrophilic film on the surface of aluminum.
Conversely, if the proportion is excessive, the film obtained is too hard, and the coated material will not be shaped easily with good abrasion resistance with dies.
- 20 The inorganic hardening agent, another component of the hydrophilic film forming composition, acts to harden ~; the alkali silicate film. The hardening agent is used in an amount of 0.1 to 5 parts by weight per part by weight of the alkali silicate. ~f the amount is , , :' ,'' "~
-` 12976~3-less than 0.1 part by weight, the alkali silicate film will not be hardened satisfactorily, whereas amounts exceeding 5 parts by weight make the film less resistant to water.
S Examples of useful inorganic hardening agents are aluminum phosphate, magnesium phosphate, tripoly-phosphoric acid and aluminum tripolyphosphate; oxides of metals such as magnesium and zirconium; carbonates, sulfates, sulfides and chlorides of polyvalent metals;
etc.
The water-soluble organic high-molecular-weight compound, another component of the present composition, acts to inhibit cement odor and to sustain the hydrophilic properties of the film over a prolonged period of time.
The water-soluble organic high-molecular-weight compound is used in an amount of 0.01 to 5 parts by weight per part by weight of the alkali silicate. If used in an amount less than 0.01 part by weight, the compound is unable to effectively prevent release of the odor and to fully sustain the hydrophilic properties. Conversely, presence of more than 5 parts by weight of the compound renders the film easily soluble in water, failing to sustain the hydrophilic properties.
Examples of useful water-soluble organic high-mole~ular-weight compounds are a) natural high-molecular-.. ..
129761;~
weight compounds of the polysaccharide type, b) naturalhigh-molecular-weight compounds of the water-soluble protein type, c) water-soluble synthetic high-molecular-weight compounds of the anionic, nonionic or cationic addi-tion polymerization type, and d) water-soluble high-molecular weight compounds of the polycondensation type.
Examples of useful polysaccharide-type compounds a) are carboxymethylcellulose, guar gum, etc.
Examples of useful protein-type compounds b) are gelatin, etc.
Examples of synthetic compounds c) of the anionic or nonionic addition polymerization type are polyacrylic acid, sodium polyacrylate, polyacrylamide, these compounds as partially hydrolyzed, polyvinyl -alcohol, polyhydroxyethyl (meth)acrylate, acrylic acidcopolymer, maleic acid copolymer, and alkali metal salts, organic amine salts or ammonium salts of these compounds.
These compounds of the addition polymerization type are also usable as carboxymethylated, sulfonated or other-wise modified.
Examples of useful synthetic compounds c) ofthe cationic addition polymerization type are polyethylene-imine, Mannich-modified compound of polyacryl-amide, diacryldimethy aluminum chloride, and polyalkyl-amino (meth)acrylates such as dimethylaminoethyl acrylate.
~' ~297613 ' Examples of useful water-soluble high-molecu~r-weight compounds of the polycondensation type are polyalkylene polyols such as polyoxyethylene glycol, polycondensation product of epichlorohydrin and a poly-amine such as ethylenediamine or hexamethyldiamine,water-soluble polyurethane resin prepared by polyconden-sation of water-soluble polyether and polyisocyanate, polyhydroxymethylmelamine resin, etc.
Preferable among the above-mentloned water-soluble organic high-molecular-weight compounds are those of the anionic addition polymerization type having a carboxylic acid group or a group of salt thereof, more preferable examples being polyacrylic acid, acrylic acid copolymer.
Examples of preferred acrylic acid copolymers and maleic acid copolymers are copolymer of acrylic acid and maleic acid, copolymer of acryIic acid or maleic acid, and methacrylic acid, methyl methacrylate, ethyl methacrylate, hydroxyethyl methacrylate, itaconic acid, vinylsulfonic acid or acrylamide, and copolymer of vinyl-sulfonic acid and acrylamide.
The composition comprising an alkali silicate, an inorganic hardening agent and a water-soluble high-molecular-weight compound is used as diluted with water or some other medium. The degree of dilution is .: ' --`' 12g76~3- .
determined in view of the desired hydrophilic properties and thickness of the film and ease of application.
To treat the surface of aluminum with an aqueous dilution of the composition (i.e. aqueous solution), the aqueous solution is applied by spraying or with a brush, or aluminum is dipped in the aqueous solution.
- The aluminum treated with the aqueous solution is heated at 50 to 200 C, preferably 150 to 180 C, for 30 seconds to 30 minutes, whereby a hydrophilic film is formed on the surface of the aluminum. If the heat-drying temperature is below 50 C, the composition fails to form a satisfactory film, while heating at a temperature above 200 C is ineffective and adversely affects the aluminum material. Fur~her if the heat-drying time is less than 30 seconds, the composition will not be made into a satisfactory film, whereas if it exceeds 30 minutes, reduced productivity will result. The treated aluminum may be heated for a short period of 30 seconds to 1 minute when a high heating temperature of 160 to 200 C
is used, while the heat-drying time needs to be extended at low temperatures. When the coating is not fully heat-dried, the composition fails to form a satisfactory film.
The hydrophilic film is formed on the surface of aluminum in an amount of 0.1 to 10 g/m , 2referably :~ .
... .. . . . .
0.5 to 3 g/m2. When in an amount of at least 0.1 g/m2, the film has good initial hydrophilic properties.
However, it is desirable to form the film in an amount of at least 0.5 g/m2 so as to assure satisfactory hydro-philic properties over a prolonged priod of time. Ifche amount exceeds lO g/m2, a longer drying time is required, and the film adversely affects the workability of the resulting material by press forming.
The aqueous solution may further incorporate therein known addititives. Examples of such additives include inorganic corrosion inhibitors such as sodium nitrite, sodium polyphosphate and sodium metaborate, and organic corrosion inhibitors such as benzoic acid or salts thereof, p-nitrobenzoic acid or salts thereof, cyclohexylamine carbonate and benzotriazole.
To give increased corrosion resistance to aluminum and to enhance the adhesion of the ~hydrophilic film to aluminum, it is desirable to form a corrosion-resistant film first on the surface of aluminum by the chromate process, phosphoric acid-chromate process, boehmite process, ~hosphate process or the like, and thereafter surface-treat the aluminum with the present composition.
Furthemore, the thin aluminum plate having the hydrophilic film of the present composition formed A
1297613 .
thereon is preferably coated with a covering layer comprising a wax or the combination of wax and polyvinyl alcohol or like water-soluble high-molecular-weight compound to reduce the wear of the die to be used for shaping the thin aluminum plate into the desired shape of fins. Use of such wax and water-soluble high-molecular-weight compound is described in detail in Unexamined Japanese Patent Publication SHO 59-118450.
The present invention will be further described with reference to examples and comparative example.
Example 1 A specimen was prepared using an aluminum plate made of JIS A-llOOH24 and measuring 1 mm in thickness, 50 mm in width and 100 mm in length.
The surface of the aluminum plate was first treated by the chromate process to form an oxide film thereon and then coated with an aqueous solution com-prising a hydrophilic film forming composition of the invention which was composed of three components in specified proportions as listed in the table below. (The solution contained 1.5~ of the listed alkali silicate calculated as solids.) The coated plate was thereafter heat-dried at 160 C for 10 minutes to form a hydrophilic film on the surface of the aluminum plate; The resulting aluminum plate was shaped into a heat exchanger fin.
:~ `
, 129'76~3 ' Examples 2 to 6 The same procedure as in Example 1 was repeated using hydrophilic film forming compositions comprising different components in different proportions as listed below.
Comparative Example The procedure of Example 1 was repeated using a film forming composition which was free from any water-soluble organic hight-molecular-weight compound.
Evaluation Test To evaluate the properties of the fins thus prepared, the fins were checked for hydrophilic properties and cement odor, with the results listed below.
For the evaluation of the hydrophilic proper-ties, the angle of contact between the fin and water wasmeasured in the initial stage, after immersing the fin in running water for 100 hours (water resistance) and after immersing the fin in oleic acid for 16 hours and in running water for 8 hours alternately, five times in each liquid (oil resistance).
The hydrophilic properties were evaluated according to the criteria of: A when the angle of contact was up to 15 degrees, and B when the angle of contact was 16 to 30 degrees. The defree of cement odor was ~; 25 determined according to the criteria of: A for no odor, , .
12976~3 ~
B for a slight odor, and C for a very strong odor.
For comparison, the same aluminum plate as used above was coated with an aqueous solution of an alkali silicate and inorganic hardening agent and then dried by heating to form an alkali silicate film on the aluminum plate. The resulting plate was evaluated in the same manner as above with the results also listed below.
m m m o aJ ~
~ o a Q~
h '-1 3 h ., h .r~
:I: H
O ~ ~ I
_ ~ O o ~
0 ~ a) ~ 1 ~ O h o rl ~1 o I ~1 a)-- ~s o ~d U ~ n _ ,~ _ u O
TITLE OF THE INVENTION
COMPOSITION FOR FORMING HYDROPHILIC FILM ON ALUMINUM
BACKGROUND OF THE INVENTION
The present invention relates to a composition for forming a hydrophilic film on aluminum, for example, on the surface of an aluminum fin material for heat exchangers and on the surface of aluminum heat exchangers comprising the combination of fins and tubes.
The term "aluminum" as used herein includes not only pure aluminum but also aluminum alloys.
Generally with heat exchangers, especially with the evaporators of room air conditioners and of air conditioners for motor vehicles, the surface temperature of the fins drops below the dew point of the atmosphere, permitting deposition of water drops on the surface of the fins. The deposition of water drops results in increased resistance to the passage of air and a reduced air flow between the fins to entail a reduced heat , i ............ .
exchange efficiency. Such phenomena occur markedly especially when the fin pitch is decreased to improve the performance of the heat exchanger and to render the exchanger smaller. The wettability of the fin surface greatly influences the heat exchange efficiency. High wettability of the fin surface makes it difficult for the condensed water vapor to form water drops, reducing the resistance to the air flow and increasing the amount of air flow to achieve a higher heat exchange efficiency.
Good wettability further prevents the water deposited on the fins from splashing and the outdoor heat exchanger from frosting.
The wettability of the surface of aluminum fins has heretofore been improved by coating the fin surface with a film using a hydrophilic resin or water glass (alkali silicate, see Examined Japanese Patent Publication SHO 53-48177).
However, thé film of the former material has the drawback of becoming gradually impaired in hydrophilic properties and failing to exhibit sustained resistance to water and oil, while the film prepared from the latter material gives off a cement odor due to the alkali silicate to lower the commercial value of the product.
In view of these problems, the ,main object of the present invention is to provide a composition for ....
~297613 forming a hydrophilic film which gives off no cement odor and which retains sustained hydrophilic properties over a prolonged period of time.
SUMMARY OF THE INVENTION
The composition of the present invention for forming a hydrophilic film on aluminum comprises an alkali silicate, an inorganic hardening agent and a water-soluble organic high-molecular-weight compound.
The hydrophilic film forming composition is used for aluminum fin materials for producing heat exchanger fins, aluminum products such as aluminum heat exchangers comprising the combination of fins and tubes, and materi-als for such products. Suitable aluminum fin materials are coiled materials which can be treated for forming a film and shaped continuously.
The water-soluble organic high-molecular-weight compound serves to effectively prevent the alkali silicate from giving off a cement odor and also to sustain over a prolonged period the hydrophilic properties of the film prepared from the alkali silicate and the inorganic hardening agent.
Thus, ~he composition of the present invention forms hydrophilic films which release no cement odor and retain sustained hydrophilic properties over a prolonged period of time.
.
: . ' , . . .
DETAILED DESCRIPTION OF THE INVENTION
Examples of useful alkali silicates as one of t:he components of the hydrophilic film forming composition are sodium silicate, potassium silicate, lithium silicate, etc.
The alkali silicate acts to impart hydrophilic properties to aluminum. The silicate to be used normally has a SiO2/M2o ratio of at least 1 wherein M is an alkali metal such as lithium, sodium or potassium. Especially preferable are alkali silicates which have a SiO2/M2O ratio of 2 to 5. If the Sio2~M2o ratio is less than 1, SiO2 is smaller than the alkali component in proportion, permitting the alkali component to corrode aluminum markedly.
Further if the proportion of the alkali silicate in the composition is small, the composition fails to form a satisfactory hydrophilic film on the surface of aluminum.
Conversely, if the proportion is excessive, the film obtained is too hard, and the coated material will not be shaped easily with good abrasion resistance with dies.
- 20 The inorganic hardening agent, another component of the hydrophilic film forming composition, acts to harden ~; the alkali silicate film. The hardening agent is used in an amount of 0.1 to 5 parts by weight per part by weight of the alkali silicate. ~f the amount is , , :' ,'' "~
-` 12976~3-less than 0.1 part by weight, the alkali silicate film will not be hardened satisfactorily, whereas amounts exceeding 5 parts by weight make the film less resistant to water.
S Examples of useful inorganic hardening agents are aluminum phosphate, magnesium phosphate, tripoly-phosphoric acid and aluminum tripolyphosphate; oxides of metals such as magnesium and zirconium; carbonates, sulfates, sulfides and chlorides of polyvalent metals;
etc.
The water-soluble organic high-molecular-weight compound, another component of the present composition, acts to inhibit cement odor and to sustain the hydrophilic properties of the film over a prolonged period of time.
The water-soluble organic high-molecular-weight compound is used in an amount of 0.01 to 5 parts by weight per part by weight of the alkali silicate. If used in an amount less than 0.01 part by weight, the compound is unable to effectively prevent release of the odor and to fully sustain the hydrophilic properties. Conversely, presence of more than 5 parts by weight of the compound renders the film easily soluble in water, failing to sustain the hydrophilic properties.
Examples of useful water-soluble organic high-mole~ular-weight compounds are a) natural high-molecular-.. ..
129761;~
weight compounds of the polysaccharide type, b) naturalhigh-molecular-weight compounds of the water-soluble protein type, c) water-soluble synthetic high-molecular-weight compounds of the anionic, nonionic or cationic addi-tion polymerization type, and d) water-soluble high-molecular weight compounds of the polycondensation type.
Examples of useful polysaccharide-type compounds a) are carboxymethylcellulose, guar gum, etc.
Examples of useful protein-type compounds b) are gelatin, etc.
Examples of synthetic compounds c) of the anionic or nonionic addition polymerization type are polyacrylic acid, sodium polyacrylate, polyacrylamide, these compounds as partially hydrolyzed, polyvinyl -alcohol, polyhydroxyethyl (meth)acrylate, acrylic acidcopolymer, maleic acid copolymer, and alkali metal salts, organic amine salts or ammonium salts of these compounds.
These compounds of the addition polymerization type are also usable as carboxymethylated, sulfonated or other-wise modified.
Examples of useful synthetic compounds c) ofthe cationic addition polymerization type are polyethylene-imine, Mannich-modified compound of polyacryl-amide, diacryldimethy aluminum chloride, and polyalkyl-amino (meth)acrylates such as dimethylaminoethyl acrylate.
~' ~297613 ' Examples of useful water-soluble high-molecu~r-weight compounds of the polycondensation type are polyalkylene polyols such as polyoxyethylene glycol, polycondensation product of epichlorohydrin and a poly-amine such as ethylenediamine or hexamethyldiamine,water-soluble polyurethane resin prepared by polyconden-sation of water-soluble polyether and polyisocyanate, polyhydroxymethylmelamine resin, etc.
Preferable among the above-mentloned water-soluble organic high-molecular-weight compounds are those of the anionic addition polymerization type having a carboxylic acid group or a group of salt thereof, more preferable examples being polyacrylic acid, acrylic acid copolymer.
Examples of preferred acrylic acid copolymers and maleic acid copolymers are copolymer of acrylic acid and maleic acid, copolymer of acryIic acid or maleic acid, and methacrylic acid, methyl methacrylate, ethyl methacrylate, hydroxyethyl methacrylate, itaconic acid, vinylsulfonic acid or acrylamide, and copolymer of vinyl-sulfonic acid and acrylamide.
The composition comprising an alkali silicate, an inorganic hardening agent and a water-soluble high-molecular-weight compound is used as diluted with water or some other medium. The degree of dilution is .: ' --`' 12g76~3- .
determined in view of the desired hydrophilic properties and thickness of the film and ease of application.
To treat the surface of aluminum with an aqueous dilution of the composition (i.e. aqueous solution), the aqueous solution is applied by spraying or with a brush, or aluminum is dipped in the aqueous solution.
- The aluminum treated with the aqueous solution is heated at 50 to 200 C, preferably 150 to 180 C, for 30 seconds to 30 minutes, whereby a hydrophilic film is formed on the surface of the aluminum. If the heat-drying temperature is below 50 C, the composition fails to form a satisfactory film, while heating at a temperature above 200 C is ineffective and adversely affects the aluminum material. Fur~her if the heat-drying time is less than 30 seconds, the composition will not be made into a satisfactory film, whereas if it exceeds 30 minutes, reduced productivity will result. The treated aluminum may be heated for a short period of 30 seconds to 1 minute when a high heating temperature of 160 to 200 C
is used, while the heat-drying time needs to be extended at low temperatures. When the coating is not fully heat-dried, the composition fails to form a satisfactory film.
The hydrophilic film is formed on the surface of aluminum in an amount of 0.1 to 10 g/m , 2referably :~ .
... .. . . . .
0.5 to 3 g/m2. When in an amount of at least 0.1 g/m2, the film has good initial hydrophilic properties.
However, it is desirable to form the film in an amount of at least 0.5 g/m2 so as to assure satisfactory hydro-philic properties over a prolonged priod of time. Ifche amount exceeds lO g/m2, a longer drying time is required, and the film adversely affects the workability of the resulting material by press forming.
The aqueous solution may further incorporate therein known addititives. Examples of such additives include inorganic corrosion inhibitors such as sodium nitrite, sodium polyphosphate and sodium metaborate, and organic corrosion inhibitors such as benzoic acid or salts thereof, p-nitrobenzoic acid or salts thereof, cyclohexylamine carbonate and benzotriazole.
To give increased corrosion resistance to aluminum and to enhance the adhesion of the ~hydrophilic film to aluminum, it is desirable to form a corrosion-resistant film first on the surface of aluminum by the chromate process, phosphoric acid-chromate process, boehmite process, ~hosphate process or the like, and thereafter surface-treat the aluminum with the present composition.
Furthemore, the thin aluminum plate having the hydrophilic film of the present composition formed A
1297613 .
thereon is preferably coated with a covering layer comprising a wax or the combination of wax and polyvinyl alcohol or like water-soluble high-molecular-weight compound to reduce the wear of the die to be used for shaping the thin aluminum plate into the desired shape of fins. Use of such wax and water-soluble high-molecular-weight compound is described in detail in Unexamined Japanese Patent Publication SHO 59-118450.
The present invention will be further described with reference to examples and comparative example.
Example 1 A specimen was prepared using an aluminum plate made of JIS A-llOOH24 and measuring 1 mm in thickness, 50 mm in width and 100 mm in length.
The surface of the aluminum plate was first treated by the chromate process to form an oxide film thereon and then coated with an aqueous solution com-prising a hydrophilic film forming composition of the invention which was composed of three components in specified proportions as listed in the table below. (The solution contained 1.5~ of the listed alkali silicate calculated as solids.) The coated plate was thereafter heat-dried at 160 C for 10 minutes to form a hydrophilic film on the surface of the aluminum plate; The resulting aluminum plate was shaped into a heat exchanger fin.
:~ `
, 129'76~3 ' Examples 2 to 6 The same procedure as in Example 1 was repeated using hydrophilic film forming compositions comprising different components in different proportions as listed below.
Comparative Example The procedure of Example 1 was repeated using a film forming composition which was free from any water-soluble organic hight-molecular-weight compound.
Evaluation Test To evaluate the properties of the fins thus prepared, the fins were checked for hydrophilic properties and cement odor, with the results listed below.
For the evaluation of the hydrophilic proper-ties, the angle of contact between the fin and water wasmeasured in the initial stage, after immersing the fin in running water for 100 hours (water resistance) and after immersing the fin in oleic acid for 16 hours and in running water for 8 hours alternately, five times in each liquid (oil resistance).
The hydrophilic properties were evaluated according to the criteria of: A when the angle of contact was up to 15 degrees, and B when the angle of contact was 16 to 30 degrees. The defree of cement odor was ~; 25 determined according to the criteria of: A for no odor, , .
12976~3 ~
B for a slight odor, and C for a very strong odor.
For comparison, the same aluminum plate as used above was coated with an aqueous solution of an alkali silicate and inorganic hardening agent and then dried by heating to form an alkali silicate film on the aluminum plate. The resulting plate was evaluated in the same manner as above with the results also listed below.
m m m o aJ ~
~ o a Q~
h '-1 3 h ., h .r~
:I: H
O ~ ~ I
_ ~ O o ~
0 ~ a) ~ 1 ~ O h o rl ~1 o I ~1 a)-- ~s o ~d U ~ n _ ,~ _ u O
3 ~1 ~1 0 1~ 0 ~
_ ~ ~ ,a ta ~x ~--~ c~~ ~ 0 ~ ~ O ~ o O ~ ~ I
--I a) ~ ~ O s~
_, o ~ ~ ~ ~o ~ ~ ~ ~ o ,, 0 o ~ ~ o ~ V ~ I s ~ ~
I ~ ~~1 0 ~~ 0 7~ _I S C~ ~ ~ ~ 0 0 h I O0 1 -1~1 1 ~1 0 1 0 ,~
O ~ ,C R0 ~5 0~ ~ 0 0 ~ ,~ ~d ' .1 ~1 ~ tJ~ ~ ~0 ~1 ~, rl ~ 0 i _I 0~rl o0 c) ot) o 0 o a) ~ o s ~ s O Z 0 ~ ~ 0 c) Z ~ ~ x 0 ~ ~ 0 e ~o ~ c:e ~ E ~
:~ 0 ~c~ s ~ 1 Y o ~ ~1 ~1 s ~1 _I Y
S ~) ~) ~ ~ 1 0 Q, ~-1 Q. O ~-- O ~J ~ O Q-- O "
s~ e 0 0~ Q, 0 0 e 0 0 ~ ~ o C4 V~ ~5 Q. 0~
o )~ a) ~ o-- ~1 o-- . o-- ~1 o ~ 1 O C, 0 ~ _1 S~ ~ S _I S ~ S ~ ~rl X h S
~ H S 0~ ~¢ ~ ~ ~ Q, ~ ~ ~ t~ O E~ ~ ~ E~
O
.,1 e e ~ ~ C) ,, ~ ~ e ~
0 ~ ~~ 0--e ~-- u~ _ 0 0_ 0 0_ o ~ ~ ~ O ~0 0 ~ U--~ 0 o ~ 0 C)--Q~ 0 ~rl ~ rl-- 0 ~I-- S ~ 1-- 0 ~
O _~ ~1 0~0 ~1 0~ 1O-rl O rl O rl c~ ~¢ 0 ~ 0 P~ 0 ~ 0 u~ 0 ~4 0 p~ 0 , ~ .
e Q.
0 ~ ~ D e -X ~I 0~
129~6~3 The above table reveals that the hydrophilic films formed on the surfac~s of the fins uslng the composi-tions of the invention have outstanding hydrophilic perperties and are almost free from any cement odor unlike the film of the comparative example.
, .. . .
_ ~ ~ ,a ta ~x ~--~ c~~ ~ 0 ~ ~ O ~ o O ~ ~ I
--I a) ~ ~ O s~
_, o ~ ~ ~ ~o ~ ~ ~ ~ o ,, 0 o ~ ~ o ~ V ~ I s ~ ~
I ~ ~~1 0 ~~ 0 7~ _I S C~ ~ ~ ~ 0 0 h I O0 1 -1~1 1 ~1 0 1 0 ,~
O ~ ,C R0 ~5 0~ ~ 0 0 ~ ,~ ~d ' .1 ~1 ~ tJ~ ~ ~0 ~1 ~, rl ~ 0 i _I 0~rl o0 c) ot) o 0 o a) ~ o s ~ s O Z 0 ~ ~ 0 c) Z ~ ~ x 0 ~ ~ 0 e ~o ~ c:e ~ E ~
:~ 0 ~c~ s ~ 1 Y o ~ ~1 ~1 s ~1 _I Y
S ~) ~) ~ ~ 1 0 Q, ~-1 Q. O ~-- O ~J ~ O Q-- O "
s~ e 0 0~ Q, 0 0 e 0 0 ~ ~ o C4 V~ ~5 Q. 0~
o )~ a) ~ o-- ~1 o-- . o-- ~1 o ~ 1 O C, 0 ~ _1 S~ ~ S _I S ~ S ~ ~rl X h S
~ H S 0~ ~¢ ~ ~ ~ Q, ~ ~ ~ t~ O E~ ~ ~ E~
O
.,1 e e ~ ~ C) ,, ~ ~ e ~
0 ~ ~~ 0--e ~-- u~ _ 0 0_ 0 0_ o ~ ~ ~ O ~0 0 ~ U--~ 0 o ~ 0 C)--Q~ 0 ~rl ~ rl-- 0 ~I-- S ~ 1-- 0 ~
O _~ ~1 0~0 ~1 0~ 1O-rl O rl O rl c~ ~¢ 0 ~ 0 P~ 0 ~ 0 u~ 0 ~4 0 p~ 0 , ~ .
e Q.
0 ~ ~ D e -X ~I 0~
129~6~3 The above table reveals that the hydrophilic films formed on the surfac~s of the fins uslng the composi-tions of the invention have outstanding hydrophilic perperties and are almost free from any cement odor unlike the film of the comparative example.
, .. . .
Claims (19)
1. A heat exchanger made of aluminum and comprising a tube and fins attached to the tube, wherein the fins are coated with a hydrophilic film having a composition consisting essentially of an alkali silicate having an SiO2/M2O (wherein M is an alkali metal) of at least 1, 0.1 to 5 parts by weight (per part by weight of the alkali silicate) of an inorganic hardening agent and 0.01 to 5 parts by weight (per part by weight of the alkali silicate) of a water-soluble high-molecular-weight organic compound.
2. A heat exchanger as defined in claim 1 wherein the composition comprises 0.1 to 0.5 part by weight of the inorganic hardening agent per part by weight of the alkali silicate and 0.5 to 2 parts by weight of the water-soluble high-molecular-weight organic compound per part by weight of the alkali silicate.
3. A heat exchanger as defined in claim 1 wherein the alkali silicate has an SiO2/M2O ratio of 2 to 5 wherein M is an alkali metal.
4. A heat exchanger as defined in claim 1 wherein the alkali silicate is a salt selected from the group consisting of sodium silicate, potassium silicate and lithium silicate.
5. A heat exchanger as defined in claim 1 wherein the inorganic hardening agent is a compound selected from the group consisting of aluminum phosphate, magnesium phosphate, tripoly-phosphoric acid, aluminum tripolyphosphate, magnesium oxide, zirconium oxide, and carbonates, sulfates, sulfides and chlorides of polyvalent metals.
6. A heat exchanger as defined in claim 1, 2, 3, 4 or 5, wherein the water-soluble organic high-molecular-weight compound is a compound selected from the group consisting of natural high-molecular-weight compound of the polysaccharide type, natural high-molecular-weight compound of the water-soluble protein type, water-soluble synthetic compound of the anionic, nonionic or cationic addition polymerization type and water-soluble high-molecular-weight compound of the polycondensation type.
7. A heat exchanger as defined in claim 6 wherein the water-soluble organic high-molecular-weight compound is carboxy-methylcellulose or guar gum.
8. A heat exchanger as defined in claim 6 wherein the water-soluble organic high-molecular-weight compound is gelatin.
9. A heat exchanger as defined in claim 6 wherein the water-soluble organic high-molecular-weight compound is a synthetic anionic or nonionic addition polymerization type compound selected from the group consisting of polyacrylic acid;
sodium polyacrylate; polyacrylamide or a partially hydrolyzed product thereof; polyvinyl alcohol; polyhydroxyethyl (meth)-acrylate; and acrylic acid copolymer, maleic acid copolymers or alkali metal salts, organic amine salts or ammonium salts of these compounds or is a modified water-soluble synthetic high-molecular-weight compound prepared by carboxymethylating or sulfonating the said synthetic high-molecular-weight compound of the addition polymerization type.
sodium polyacrylate; polyacrylamide or a partially hydrolyzed product thereof; polyvinyl alcohol; polyhydroxyethyl (meth)-acrylate; and acrylic acid copolymer, maleic acid copolymers or alkali metal salts, organic amine salts or ammonium salts of these compounds or is a modified water-soluble synthetic high-molecular-weight compound prepared by carboxymethylating or sulfonating the said synthetic high-molecular-weight compound of the addition polymerization type.
10. A heat exchanger as defined in claim 6 wherein the water-soluble organic high-molecular-weight compound is a cationic addition polymerization type compound selected from the group consisting of polyethyleneimine, Mannich-modified compound of polyacrylamide, diacryldimethyl aluminum chloride and polyalkyl-amino (meth)acrylate.
11. A heat exchanger as defined in claim 6 wherein the water-soluble high-molecular-weight compound is a polycondensation type compound selected from the group consisting of polyalkylene polyol, polycondensation product of polyamine and epichlorohydrin, and water-soluble polyurethane resin prepared by the poly-condensation of water-soluble polyether and polyisocyanate and polyhydroxymethylmelamine resin.
12. A heat exchanger made of aluminum and comprising a tube and fins attached to the tube, wherein the fins are coated with a hydrophilic film having a composition consisting essentially of:
an alkali metal silicate having an SiO2/M2O ratio of at least 1 and not more than 5, where M is an alkali metal;
an inorganic hardening agent in an amount of 0.1 to 5 parts by weight per part by weight of the alkali metal silicate;
and a water-soluble high-molecular-weight organic compound in an amount of 0.01 to 5 parts by weight per part of the alkali metal silicate.
an alkali metal silicate having an SiO2/M2O ratio of at least 1 and not more than 5, where M is an alkali metal;
an inorganic hardening agent in an amount of 0.1 to 5 parts by weight per part by weight of the alkali metal silicate;
and a water-soluble high-molecular-weight organic compound in an amount of 0.01 to 5 parts by weight per part of the alkali metal silicate.
13. A method of forming a hydrophilic film on a surface of an article made of aluminum or aluminum alloy, which method comprises:
treating the surface of the article with an aqueous composition comprising an alkali metal silicate, an inorganic hardening agent and a water-soluble organic high-molecular-weight compound, and heating the thus-treated article at 50 to 200°C, thereby forming the film, wherein the alkali metal silicate has an SiO2/M2O ratio of at least 1 in which M is an alkali metal;
- 18a - 25088-67 the hardening agent is used in an amount of 0.1 to 5 parts by weight per part of the alkali metal silicate and is selected from the group consisting of aluminum phosphate, magne-sium phosphate, tripolyphosphoric acid, aluminum tripolyphosphate, magnesium oxide, zirconium oxide, and carbonate, sulfate, sulfide or chloride of polyvalent metals; and the water-soluble organic high-molecular-weight compound is used in an amount of 0.01 to 5 parts by weight per part of the alkali metal silicate and is selected from the group consisting of a) natural water-soluble polysaccharides, b) natural water-soluble protein, c) a water-soluble synthetic anionic, nonionic or cation-ic addition polymerization, and d) a water-soluble synthetic poly-condensation product.
treating the surface of the article with an aqueous composition comprising an alkali metal silicate, an inorganic hardening agent and a water-soluble organic high-molecular-weight compound, and heating the thus-treated article at 50 to 200°C, thereby forming the film, wherein the alkali metal silicate has an SiO2/M2O ratio of at least 1 in which M is an alkali metal;
- 18a - 25088-67 the hardening agent is used in an amount of 0.1 to 5 parts by weight per part of the alkali metal silicate and is selected from the group consisting of aluminum phosphate, magne-sium phosphate, tripolyphosphoric acid, aluminum tripolyphosphate, magnesium oxide, zirconium oxide, and carbonate, sulfate, sulfide or chloride of polyvalent metals; and the water-soluble organic high-molecular-weight compound is used in an amount of 0.01 to 5 parts by weight per part of the alkali metal silicate and is selected from the group consisting of a) natural water-soluble polysaccharides, b) natural water-soluble protein, c) a water-soluble synthetic anionic, nonionic or cation-ic addition polymerization, and d) a water-soluble synthetic poly-condensation product.
14. A method as defined in claim 13, wherein the article is to be shaped into heat exchanger fins.
15. A composition for forming a hydrophilic film on alumin-um, which is an aqueous composition comprising an alkali metal silicate, an inorganic hardening agent and a water-soluble organic high-molecular-weight compound, wherein the alkali metal silicate has an SiO2/M2O ratio of at least 1 in which M is an alkali metal;
the hardening agent is used in an amount of 0.1 to 5 parts by weight per part of the alkali metal silicate and is selected from the group consisting of aluminum phosphate, magne-sium phosphate, tripolyphosphoric acid, aluminum tripolyphosphate, magnesium oxide, zirconium oxide, and carbonate, sulfate, sulfide or chloride of polyvalent metals;
and the water-soluble organic high-molecular-weight compound is used in an amount of 0.01 to 5 parts by weight per part of the alkali metal silicate and is selected from the group consisting of a) natural water-soluble polysacchar-ides, b) natural water-soluble protein, c) a water-soluble synthetic anionic, nonionic or cationic addition polymerization and d) a water-soluble synthetic polycondensation product.
the hardening agent is used in an amount of 0.1 to 5 parts by weight per part of the alkali metal silicate and is selected from the group consisting of aluminum phosphate, magne-sium phosphate, tripolyphosphoric acid, aluminum tripolyphosphate, magnesium oxide, zirconium oxide, and carbonate, sulfate, sulfide or chloride of polyvalent metals;
and the water-soluble organic high-molecular-weight compound is used in an amount of 0.01 to 5 parts by weight per part of the alkali metal silicate and is selected from the group consisting of a) natural water-soluble polysacchar-ides, b) natural water-soluble protein, c) a water-soluble synthetic anionic, nonionic or cationic addition polymerization and d) a water-soluble synthetic polycondensation product.
16. A method of claim 14, wherein the water-soluble high-molecular-weight compound is polyvinyl alcohol;
polyacrylic acid or an alkali metal or ammonium salt thereof;
polyacrylamide; polyhydroxy (meth)acrylate; an acrylic acid copolymer or an alkali metal or ammonium salt thereof; or a maleic acid copolymer or an alkali metal or ammonium salt thereof.
polyacrylic acid or an alkali metal or ammonium salt thereof;
polyacrylamide; polyhydroxy (meth)acrylate; an acrylic acid copolymer or an alkali metal or ammonium salt thereof; or a maleic acid copolymer or an alkali metal or ammonium salt thereof.
17. A method of claim 14, wherein the water-soluble high-molecular-weight compound is an alkali metal salt of acrylic acid-acrylamide copolymer; an alkali metal salt of acrylic acid-hydroxyethyl methacrylate copolymer; an alkali metal salt of maleic acid-acrylamide copolymer;
polyethyleneimine; or vinylsulfonic acid-acrylamide copolymer.
polyethyleneimine; or vinylsulfonic acid-acrylamide copolymer.
18. A composition of claim 15 wherein the water-soluble high-molecular-weight compound is an alkali metal salt of acrylic acid-acrylamide copolymer; an alkali metal salt of acrylic acid-hydroxyethyl methacrylate copolymer; an alkali metal salt of maleic acid-acrylamide copolymer;
polyethyleneimine; or vinylsulfonic acid-acrylamide copolymer.
polyethyleneimine; or vinylsulfonic acid-acrylamide copolymer.
19. An article of aluminum or aluminum alloy having a hydrophilic film on a surface thereof, prepared by the process of claim 13, 16 or 17.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61077830A JPS62235477A (en) | 1986-04-03 | 1986-04-03 | Hydrophilic film forming agent for aluminum |
| JP77830/86 | 1986-04-03 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1297613C true CA1297613C (en) | 1992-03-17 |
Family
ID=13644956
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000533702A Expired - Fee Related CA1297613C (en) | 1986-04-03 | 1987-04-02 | Composition for forming hydrophilic film on aluminum |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US4957159A (en) |
| EP (1) | EP0240940A3 (en) |
| JP (1) | JPS62235477A (en) |
| AU (1) | AU589506B2 (en) |
| CA (1) | CA1297613C (en) |
Families Citing this family (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07109355B2 (en) * | 1986-05-20 | 1995-11-22 | 日本パ−カライジング株式会社 | Aluminum heat exchanger and manufacturing method thereof |
| NO170626C (en) * | 1990-05-18 | 1992-11-11 | Norsk Proco As | NON-PROTECTED, WATERPROOF AND ACID RESISTANT PRODUCT |
| US5356977A (en) * | 1993-05-14 | 1994-10-18 | Henkel Corporation | Hydrophilicizing sealer treatment for metal objects |
| US5514478A (en) * | 1993-09-29 | 1996-05-07 | Alcan International Limited | Nonabrasive, corrosion resistant, hydrophilic coatings for aluminum surfaces, methods of application, and articles coated therewith |
| JPH07268274A (en) * | 1994-04-01 | 1995-10-17 | Kansai Paint Co Ltd | Composition and method for imparting hydrophilicity |
| JP2001164175A (en) * | 1999-12-09 | 2001-06-19 | Kansai Paint Co Ltd | Hydrophilifying agent for heat-exchanger fin material |
| US6358616B1 (en) | 2000-02-18 | 2002-03-19 | Dancor, Inc. | Protective coating for metals |
| US6659171B2 (en) * | 2001-03-27 | 2003-12-09 | Nippon Paint Co., Ltd. | Hydrophilic modification method and heat exchanger treated thereby |
| FR2837218B1 (en) * | 2002-03-18 | 2005-02-18 | Dacral Sa | METAL SUBSTRATE COATING COMPOSITION |
| EP1489146B1 (en) * | 2002-03-27 | 2012-11-14 | Sumitomo Osaka Cement Co., Ltd. | Process for producing a hydrophilic film |
| JP2003301273A (en) * | 2002-04-10 | 2003-10-24 | Nisshin Steel Co Ltd | Metal sheet with hydrophilic coating |
| JP4787907B2 (en) * | 2009-08-27 | 2011-10-05 | 丸善薬品産業株式会社 | Hydrophilic coating agent and method of using the same |
| JP5056887B2 (en) * | 2010-03-29 | 2012-10-24 | 株式会社デンソー | Heat exchanger manufacturing method and heat exchanger manufactured thereby |
| KR20120054321A (en) * | 2010-11-19 | 2012-05-30 | 엘지전자 주식회사 | Heat pump |
| JP5793046B2 (en) * | 2011-10-06 | 2015-10-14 | 三菱アルミニウム株式会社 | Aluminum fin material for heat exchanger and heat exchanger |
| JP6030300B2 (en) * | 2011-12-28 | 2016-11-24 | 三菱アルミニウム株式会社 | Heat exchanger manufacturing method using pre-coated fin material and heat exchanger |
| JP6126340B2 (en) * | 2012-07-31 | 2017-05-10 | 三菱アルミニウム株式会社 | Fin material for heat exchanger and heat exchanger |
| JP6529749B2 (en) * | 2014-11-26 | 2019-06-12 | 三菱アルミニウム株式会社 | Heat exchanger and method of manufacturing heat exchanger |
| WO2016167928A1 (en) | 2015-04-15 | 2016-10-20 | Henkel Ag & Co. Kgaa | Thin corrosion protective coatings incorporating polyamidoamine polymers |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3926905A (en) * | 1973-06-13 | 1975-12-16 | Osaka Soda Co Ltd | Flame retardant hardenable composition of water glass and decorative products made by using the same |
| AU3039777A (en) * | 1976-11-11 | 1979-05-17 | Ppg Industries Inc | Silicate-based coating compositions |
| EP0016298B1 (en) * | 1979-01-22 | 1983-08-17 | Ball Corporation | A solution for imparting tarnish resistance on aluminium surfaces and method for applying it |
| US4341878A (en) * | 1979-01-22 | 1982-07-27 | Ball Corporation | Compositions for treating aluminum surfaces for tarnish resistance |
| US4462842A (en) * | 1979-08-13 | 1984-07-31 | Showa Aluminum Corporation | Surface treatment process for imparting hydrophilic properties to aluminum articles |
| JPS5639391A (en) * | 1979-09-04 | 1981-04-15 | Mitsubishi Electric Corp | Bearing device |
| AU520693B2 (en) * | 1979-09-10 | 1982-02-18 | Ppg Industries, Inc. | Curable pigmented silicate coating commpositions |
| US4351883A (en) * | 1980-06-23 | 1982-09-28 | Ball Corporation | Compositions for treating aluminum surfaces for tarnish resistance |
| JPS60101156A (en) * | 1983-11-07 | 1985-06-05 | Sanyo Chem Ind Ltd | Hydrophilic film-forming agent for aluminum |
| JPS60221582A (en) * | 1984-04-07 | 1985-11-06 | Kobe Steel Ltd | Aluminum fin material for heat exchanger |
-
1986
- 1986-04-03 JP JP61077830A patent/JPS62235477A/en active Granted
-
1987
- 1987-03-31 AU AU70791/87A patent/AU589506B2/en not_active Ceased
- 1987-04-02 CA CA000533702A patent/CA1297613C/en not_active Expired - Fee Related
- 1987-04-02 EP EP87104903A patent/EP0240940A3/en not_active Withdrawn
-
1989
- 1989-03-15 US US07/323,741 patent/US4957159A/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0448875B2 (en) | 1992-08-07 |
| AU589506B2 (en) | 1989-10-12 |
| US4957159A (en) | 1990-09-18 |
| EP0240940A3 (en) | 1989-09-06 |
| JPS62235477A (en) | 1987-10-15 |
| EP0240940A2 (en) | 1987-10-14 |
| AU7079187A (en) | 1987-10-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1297613C (en) | Composition for forming hydrophilic film on aluminum | |
| JP3802559B2 (en) | Non-abrasive, corrosion-resistant hydrophilic coating on aluminum surface, coating method and coating | |
| US4588025A (en) | Aluminum heat exchanger provided with fins having hydrophilic coating | |
| AU746200B2 (en) | Process for surface-treating an aluminium containing metal | |
| US4828616A (en) | Surface treatment chemical for forming a hydrophilic coating | |
| JP4008620B2 (en) | Aluminum alloy heat exchanger | |
| US3846182A (en) | Method of forming a hydrophilic coating over an aluminum surface | |
| MXPA01004838A (en) | Hydrophilizing agent for metallic material, hydrophilizing fluid, method of hydrophilizing, metallic material, and heat exchanger. | |
| KR940002833B1 (en) | Aluminum fin material for heat exchanger | |
| JP2018095850A (en) | Antifouling highly hydrophilic baked coating, method for producing the same, and aluminum fin material for heat exchanger, heat exchanger and cold apparatus | |
| JP2857343B2 (en) | Method for producing resin-based precoated fin material for heat exchanger having excellent hydrophilicity | |
| JP3836742B2 (en) | Hydrophilization method and heat exchanger subjected to hydrophilic treatment | |
| JPH086063B2 (en) | Hydrophilic surface treatment agent and treatment method | |
| JP2000262968A (en) | Surface treated fin material | |
| CA2207534A1 (en) | Aluminum surface treatment agent, treatment method, and treated aluminum | |
| JP2683812B2 (en) | Heat exchanger with aluminum fins | |
| CA1319571C (en) | Treatment method for imparting antimicrobial and hydrophilic properties to aluminum surfaces | |
| JPH06264003A (en) | Method of surface treatment for imparting mildewproofness and hydrophilicity to aluminum material | |
| JPH07323500A (en) | Aluminum-containing metal composite material and manufacture thereof | |
| JP4357059B2 (en) | Aluminum-containing metal heat exchanger with excellent long-term corrosion resistance and manufacturing method | |
| JPH0719776A (en) | Aluminum-containing metal composite for heat exchanger | |
| JP2787253B2 (en) | Aluminum heat exchanger or hydrophilic film forming agent for its fin material | |
| JP3158989B2 (en) | Heat exchanger components | |
| JP7193443B2 (en) | Aluminum fin stock | |
| JPH0818004B2 (en) | Method for hydrophilic treatment of aluminum surface |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |